Munir Akram
Here, Akram, Pakistan's ambassador to the United Nations, explains why Pakistan decided it was in its strategic interest to cooperate with the United States in the war against terror, even though it had been one of three countries that recognized the Taliban prior to 9/11. He argues that Pakistan is the only U.S. ally in the region committed to and capable of delivering a long-term campaign against extremism. "You press us more, you pressurize Pakistan, you destabilize Pakistan, it's going to be the most counterproductive thing that would happen," he warns.

Richard Armitage
In this interview, Armitage, who served as deputy secretary of state in George W. Bush's first administration, outlines why he believes the current situation in Afghanistan is "a little more dire than we've seen it publicly portrayed" and why he thinks the stability of three nations -- Afghanistan, Pakistan and India -- is at stake. He also recounts his now-infamous Sept. 12, 2001, conversation with Pakistani intelligence chief Gen. Mahmood Ahmed in which he outlined a series of "arduous and onerous" demands on Pakistan. He recalls saying: "No American will want to have anything to do with Pakistan in our moment of peril if you're not with us. It's black or white."

Steve Coll
A correspondent for The New Yorker, Coll is the Pulitzer Prize-winning author of Ghost Wars: The Secret History of the CIA, Afghanistan and Bin Laden, From the Soviet Invasion to September 10, 2001. Here, he recounts how the Taliban organized and gained power in Afghanistan with assistance from Pakistani intelligence, and how some in Pakistan's intelligence community were reluctant to switch their allegiance after President Musharraf made the decision to ally with the U.S. after 9/11. He also describes the complicated balancing act that has resulted from this decision, describing Musharraf as a "weak" U.S. ally. "The next attack against the United States may well have roots in this failed state or emerging failed state," he warns. "What are the U.S. and its allies going to do about this problem then, and why isn't it being addressed now?"

Ryan Crocker
Crocker has been the U.S. ambassador to Pakistan since October 2004. He has also served as deputy assistant secretary of state for Near Eastern Affairs. In this interview, Crocker defends Pakistan's military efforts in the tribal areas, but he argues that striking deals with militant leaders is a bad idea. Crocker also expresses a firm belief that Pakistani President Pervez Musharraf is a solid U.S. ally. "He's come forward with a comprehensive strategy designed to solve the immediate problem of cross-border attacks on coalition forces, presence of Al Qaeda and other foreigners, and attacks against the Pakistani authority, both civil and military," he explains. "But beyond that, he's looking to a long-term stabilization of the [tribal] region that will make it an integral part of the state. … That is crucial to the war on terror."

Gen. Pervez Musharraf
After taking power in a bloodless coup in 1999, Musharraf declared himself president of Pakistan in June 2001. After the Sept. 11 attacks, Musharraf became a key ally to the United States in the war on terror. Five years later, he is subject to increasing criticism from the United States that Pakistan has not done enough to stop the Taliban's resurgence, as his country continues to be a base for terror plots, including the plot to blow up airplanes bound for the United States revealed in the summer of 2006. He also faces increasingly difficult challenges on the domestic front, from inflation to ethnic disturbances to calls for democratization. In this interview, Musharraf admits that the Taliban have taken hold in areas near the Afghan border, but he defends his military's efforts in the region as well as his intelligence service's success in arresting Al Qaeda leaders.

Barnett Rubin
Author of several books on Afghanistan, Rubin is director of studies and a senior fellow at New York University's Center on International Cooperation. In 2001, he served as an adviser to Lakhdar Brahimi, the U.N.'s special representative for Afghanistan. Here, Rubin outlines Afghanistan's geostrategic importance to Pakistan and argues that U.S. policy is doomed to fail unless policymakers understand the regional politics. "I cannot really overstate how important the stakes are," he tells FRONTLINE. "A U.S. military leader in Afghanistan said to me just last week that if we do not find a way to stabilize the border between Afghanistan and Pakistan, the United States will always be at risk."

Amrullah Saleh
Head of Afghanistan's National Security Directorate (NSD), the country's intelligence service, Saleh previously served as an intelligence aide to the legendary Northern Alliance leader Ahmed Shah Massoud, who was assassinated by Al Qaeda operatives on Sept. 9, 2001. In this rare interview, Saleh accuses "proxy forces created by Pakistan" of trying to destabilize Afghanistan. He recounts an incident in which he gave Pakistani President Pervez Musharraf a list of Taliban commanders, their addresses and phone numbers; he says Pakistan did not act on the intelligence. Saleh tells FRONTLINE he does not believe the Taliban will succeed in undermining the legitimacy of the new Afghan government. "This nation has tasted the Taliban," he explains. "They were here. They do not, in their vision, promise anything bright for the future."

Peter Tomsen
Tomsen served as President George H.W. Bush's special envoy and ambassador to the Afghan resistance from 1989 to 1992. Here he lays out the historical background of the Taliban's rise to power and its relationship with Pakistani intelligence, known by its acronym ISI. He also explains the two fears driving Pakistan's Afghanistan policy -- India and Pashtun nationalism. Tomsen believes the ISI knows exactly where Osama bin Laden and his deputy Ayman al-Zawarhiri are hiding, and that Pakistani President Pervez Musharraf is not fully cooperating with the U.S. "I don't think we're getting our money's worth, and I think we have to take a tougher line," he tells FRONTLINE.